Telephone



Nov. 24, 1936'. FjARNoLg 2,062,019

' TELEPHONE Filed Nbv. 19, 19:54

Patented Nov; 24, 1936 v UNITED STATES PATENT OFFICE TELEPHONE 'Franc Arnold, St. Louis, Mo., assignor of threetenths to Benjamin M. Vogel, St. Louis, Mo.

Application November 19, 1934, Serial No. 753,620

'7 Claims. (Cl. 179-84) My invention relates to improvements in teletailed description, and specifically pointed out in phones. the appended claims.

One object of my invention is to provide an Reference is made to the accompanying drawelectrical hook-up or electrical circuit which ing for an illustrative embodiment of the incan be connected with and to the present televention.

phone circuit or electrical hook-up so that a Figure l is a front elevation of the lower porwarning or signal can be given to a person ention of the telephone embodying'my invention. gaged in conversation on the telephone to let Figure 2 is a side elevation of the lower porthat person so talking over the telephone know tion of the telephone embodying my invention. that a. third person is attempting to call him. Figure 3 is an enlarged front elevation, with 1 Another object of my invention is to provide the cover removed, of the casing enclosing the a signal or warning device which can be installed operating parts of the invention, portions thereon a telephone which will indicate or warn a of being shown in section, and the receiver hook person using the telephone that a-third person being shown diagrammatically. v is calling him. Figure 4 is a wiring diagram of the central 15 A further object of my invention is to provide telephone exchange showing two receivers and a signal or warning device which can be installed the wiring diagram of my invention attached to on a telephone which will indicate to the person the receivers and the wiring diagram of the using .the telephone or inform him that a long hook-up or circuit in the central exchange which distance call is awaiting him. sets the operating parts of my invention in The telephone circuit or hook-up -at present operation. does not provide any means or method of in- Referring to the accompanying drawi g. in

forming a person engaged in talking over a. tele- Figure l, the call waiting indicator A is shown phone that some other person is trying to reach attached to the lower portion of a telephone 2. him. The third person who tries to communi- The circular opening in the cover of the indicator 25 cate with a person so engaged in talking over 6 allows the person using the telephone to see a telephone receives a buzz through his'receiver what color is showing. The removable cover 4 is which informs him that the person called is busy. held in place by the screws 5 which are counter- The call may be of vital importance to the persunk in the removable cover 4. 0 son engaged in conversation over the phone, yet The call waiting indicator A, in Figure 2, has he is unaware that some third party is attempta pivot pin 30 extending through a vertical slot ing to reach him. A long distance call may be 3| in the rear wall 3a of the casing 3 which is made and the same held up for a long time due I attached or pivoted at 32 to the lower end of to the fact that the person for whom it is inthe arm 33. The lower arm 33', in Figure 3, is

tended cannot be informed because he is enpivotally connected at 34 to the receiver hook gaged in talking over his telephone. 35 of the telephone shown diagrammatically. My invention will remedy these deficiencies The r ".eiver hook 35 is pivotally fixed at 35a, and defects. It will provide the means of sigin Figure 3, shown diagrammatically. naling or warning the person engaged in con- The casing 3 as shown in Figures 1 and 2 is versation over the telephone that a. local or long integral with the base of telephone I and up- 40 distance call is awaiting him. After he is so right standard 2; however, this casing 3 may be warned, he of course then has the option of attached or fastened to another part of a telequickly ending his present conversation or conphone by means of a bracket or other device as tinuing with it. If he decides upon the latter, desired. v the person attempting to communicate with him The call waiting indicator A in Figure 3 is com- 45 will receive the present busy signal and have to posed of a solenoid or wire coil having a core l0. call again if he so desires. This wire coil 9 receives an electrical charge or My invention consists of a simple electrical impulse through the wires 33 and 40 which are device which is easily attached to the present attached to the receiver circuit of both C and telephone. The electrical hook-up and wires D shown in Figure 4. In Figure 3, the call in- 50 now used will, in addition to their regular uses. dicator A is enclosed by the casing 3. The wire sumce to produce the'result so desired and gencoil 3 is supported by the U shaped bracket 1 erally described above. through which the rod I I extending through and The foregoing and other objects of my invenfrom the core I0 is allowed to move. The plate tion will be made manifest in the following dei2 is affixed by solder or other means to the rod 55 I land is divided into three portions, the surfaces 4 of which are colored blue l3, red l4, and white l5. These colors can be seen through the open 'ing in the cover 6 or the call waiting indicator A and shown by dotted lines in Figure 3.

When the rod I I, in Figure 3, is expelled from the wire coil 9, the collar 6 attached to the other end of the rod compresses the spring i9 contained in the tube II. This spring may be adjusted by turning the screw 2| which is adjustable. The collar 20 on the screw 2| holds the spring in place. i

The wire coil 9, when sufliciently charged by electricity, will expel the rod so that the red surface M of the plate l2 will occupy the same position in reference to the openingin the cover 6 as the white surface l5-now does as shown in Figure 3. At the same time, the finger 22 which is attached to the plate |2 moves along the bar 24 unBl it is caught in the notch 23 which catches the finger 22 when the bar 24 is forced upward by the pressure of the leaf spring 24a. The bar 24 has two notches 23 and ispivoted at 25 to a bracket 26 fixed to the bottom wall 21. The opposite end of the bar 24 has a hammer 23 which I strikes the bell 29 fixed to the integral partition I8 of the call waiting indicator A in Figure 3. Each time the bar 24 moves upward, the hammer 28 strikes the bell 29.

The wire coil 9, when given an additional charge or charges, will expel the rod so that the blue surface of-plate I2 is in the placeof the white surface l5. The finger 22 then slides along the bar 24 past the first notch to the second notch 23 and-at the same time the bell 29. is struck twice by the hammer 28 which is caused to move up and down two times by the pressure of the leaf spring 24a against the bar 24.

When the person using the telephone has finished and hangs the receiver upon the hook 35, the arm 33 is forced downward and the pivot pin 30 forces the bar 24 downward releasing the finger 22 from the notch 23.' The spring I! then presses the collar I6 and the rod back into its original position. The plate l2, then assumes its original position and the white surface l5 can be seen through the cover opening 6. V

In Figure 4 is shown the exchange telephone circuit. This circuit is old and for that reason not described in detail. When a third party attempts to call either C or D, these parties or either of them can be signalled or warned by their call waiting indicators A which will be set in operation by the waiting call key 43. The waiting call keycircuit E in Figure 4 receives its AC source at 4| which is sent, through the resister 44 to the key 43. If the call is a local call and the color red of call waiting indicator sodesignates a local call, the operator at the central station will press the key 43 upward, and if the call is distant and the'color blue of call waiting indicator so designates a distant call, the operator at the central station will press the key 43 downward, and at the same time the operator will press the selector key 45 upward if the thirdparty is trying to call receiver C and downward if the third party is trying to call receiver D. p r

When the waiting call key 431s pressed upward, an A. C. current of 5000 c. p. s. (or-the desired frequency) from the source 4| (in- Figure 4) will flow into the primary circuit of the C (if the third party is trying to call C) by means of the telephone lines, two in number.

The filter units 36 are tuned to a certain desired frequency and the blocking condensers 3! prevent any D. C. current from getting into the circuit. The filter unit 36, the blocking condenser 31, and the call waiting indicator A as shown in Figure 4 are all tuned to the frequencies generated at the central oflice. Because of this, when the current reaches them, the call waiting indicator A will respond to this A. C. signal and,

a as shown in Figure 3, the rod I I will push the Plate |2 so that the red surface I 4 will be seen through the opening of the cover 6. At the same time an extra contact on waiting call key 43 shorts out the telephone lines going to receiver circuit D through the use of selector key 45.- 1 In Figure 4, the wires 46, 41, 48 connect the waiting call key circuit to the regular exchange circuit B. The wires so, as, and 4a in c and n connect the call waiting indicator mechanism to the receivers C and D.

If a third party wishes to call Dor C to'inform them that a long distance call is awaiting the one or the other, the waiting call key 43 will be pressed downward which will send the proper frequency of A. C. current into the primary circuit of repeating coil 4| which will introduce an i A. C. voltage in the secondary circuit of 4| which in turn will be transferred to receiver C if the central operator wishes the receiver C to be 3 notified and/or to receiver D if he should be informed. Which ever receiver is to be informed, the other will not know of the signal because the lines to his telephone are shorted out by the proper regulation of the selector key 45 by the operator.

The foregoing specifications describe how a person engaged in conversation with another person over a telephone can be notified that a local or long distance call is awaiting him. Of course,

the person can disregard the notification and external devices and/or any other type or kind of signal may be used in place of the color plate and bell herein described, all without departing from the scope of the invention. The call waiting indicator can be adopted and used and .appiled on any system whether automatic or operated by human operators. In the event the call waiting indicator is applied to an automatic system of telephone exchange, the same result can be obtained by the use of a time switch affixed to a contact of the relay switch which sets oiI busy signal.. The time switch will prevent the busy signal from being given for 15 seconds or any other specified period oftime, and at the same time will press the waiting 0011 key 43 and the selector key 43 as shown in Figure 4 so that the proper notification will be given to the proper party as described above. I

Having described my invention, what I claim as new and desire to secure and protectb Let.

ters Patent. i s:-

tends which, when allowed to move upward, will strike a bell; the said bar assuming its original position when the arm of the telephone hook is brought down.

7 2. The combination with a telephone having a hook, a call-waiting indicator comprising-a solenoid coil, a rod adapted to be shifted by the coil, an indicator operatively associated with the rod and adapted to be shifted thereby to indicating position, means normally urging the indicator toward inactive position, an audible signal device, actuating meansjor operating the same; including'a shiftable member provided with a notch, a projectioncarried by said rod and adapted to engage said notch when the rod is moved as aforesaid. in order to actuate said audible signal device, and means operatively associated with the telephone hook to detach said audible signal device when the hook is depressed.

3. The combination, with a telephone system, including a transmitter-receiver station adapted to be connected with another transmitter-receiver station of the system, of a waiting call keying circuit comprising a repeating coil, waiting call key and selector key operatively associated with said system and adapted .to transfer an operating impulse upon receiving a call for said transmitterreceiver station when connected with another station of the system, and call-waiting indicator means comprising a solenoid coil energized in response to the transfer of said impulse in said circuit, a shiftable colored plate and a bell-ringing device operatively associated with the coil and adapted to be actuated when the same is energized to give a visual and an audible indication that a call is awaiting connection.

4. The combinatiomwith a telephone system,

-including a transmitter-receiver station adapted to be connected with another transmitter-receiver station of the system, of a waiting call keying circuit comprising a repeating coil, waiting call key and-selector key operatively associated with said system and adapted to transfer an operating impulse upon receiving a call for said transmitter-receiver station when connected with another station of the system, and call-waiting indicator means comprising a solenoid coil energized in response to the transfer of said impulse in said circuit, indicator means shiftable when the coil in energized to indicate that a coil is waiting connection, and audible attention attracting means operable contemporaneously with the indicator.

5. The combination, with a telephone system,

I including atransmitter-receiver station adapted to be connected with another transmitterreceiver station of the system, of a waiting call keying circuit comprising a repeating coll, waiting call key fer an operating impulse upon and selector key operatively as--- sociated with said system and adapted to transreceiving a call for said transmitter-receiver station when con-' nected with another station of the system, and call-waiting indicator means comprising a solenoid coil energized in response to the transfer of said impulse insaid circuit and a colored plate shiftable when the coil is energized to indicate that a call is waiting connection.

6. The combination, with a telephone system, including a'transmitter-receiver station adapted to be connected with another transmitter-receiver'stationv of the system, of a waiting call keying circuit comprisinga'repeating coil, waiting call key and selector key operatively associated with said system and adapted to transfer an operating impulse upon receiving a call for said transmitter-receiver station when connected with another station of the system, and call' waiting indicator means comprising a solenoid coil energized in response to the transfer of said impulse in said circuit, and indicating means actuated by said solenoid coil when energized.

7. The combination, with a telephone system, including a transmitter-receiver station adapted to be connected with another transmitter-receiver station of the system, of a waiting call indicator circuit comprising a solenoid coil at the transmitter-receiver station, means including selector mechanism and a waiting call key operatively as-' --sociated with and adapted to energize said sole- 

